1. Field of the Invention
The present invention relates to an automatic flash amount control apparatus of camera which meters a flash amount with a field to be photographed being divided into a plurality of regions so as to execute flash amount control according to results of the metering.
2. Related Background Art
Suppose that synchro-flash photography is carried out in the daytime with a camera having a TTL automatic flash amount control apparatus. If there exists an object with high brightness such as the sun or the like in a portion of a photographic screen, a flash amount of an electronic flash device is so influenced thereby as to decrease, resulting in under-exposure of a main subject. An automatic flash amount control apparatus of camera is proposed to prevent the under-exposure in U.S. Pat. No. 5,006,879, wherein flash control regions and contribution rates (weights) to be used upon flashing are determined according to metering outputs of stationary light metered by dividing a field to be photographed. According to such a camera, a high brightness region where the sun or the like exists may be excluded from the regions for controlling the flash amount, so that the under-exposure may be effectively prevented.
It is, however, general in flash photography that a region to be illuminated by flash, which is a region where a main subject exists, occupies only a portion of the screen. If there are many regions to be used in controlling the flash amount, a region where the main subject does not exist, which is a region with relatively low brightness because the high brightness region is the already cut, is included in the regions to be used in controlling flash amount. It is thus likely to result in over-exposure of a main subject in the above-mentioned conventional apparatus.